MX2007001813A - Method of making vapour deposited oxygen-scavenging particles. - Google Patents

Abstract

This invention discloses a method of making an oxygen scavenging particle comprised of an activating component and an oxidizable component wherein one component is deposited upon the other component from a vapour phase and is particularly useful when the activating component is a protic solvent hydrolysable halogen compound and the oxygen scavenging particle is a reduced metal.

Description

METHOD OF MANUFACTURE OF PARTICLES OF OXYGEN SCRAPERS DEPOSITED BY MEANS OF STEAM INTERREFERENCE WITH RELATED REQUESTS This patent application claims the priority benefit of U.S. Provisional Patent Application Serial No. 60/601, 268, filed on August 13, 2004, the teachings of which are incorporated in the present specification.

FIELD OF THE INVENTION This invention relates to oxygen scavenger particles and methods for their manufacture which have utility in packaging, particularly suitable for incorporation into film-forming polymers, preferably aromatic polyester resins, and into the wall of a container made of the aromatic polyester that contains the sweeping particle.

DESCRIPTION OF THE RELATED TECHNIQUE Oxygen-sensitive products, particularly food, beverages and medicines, deteriorate or spoil in the presence of oxygen. One approach to reduce these difficulties is to package such products in a container comprising at least one layer of a "passive" gas barrier film, which acts as a physical barrier and reduces or eliminates the transmission of oxygen through the container wall, but does not react with oxygen. Another approach to achieving or maintaining a low oxygen medium within a package is to use a package containing a fast-acting oxygen-absorbing material. The package, also referred to as a bag or sack, is placed inside the package along with the product. The oxygen absorbing material in the bag protects the packaged product by reacting with the oxygen before the oxygen reacts with the packaged product. Although the oxygen absorbers or sweeping materials used in the packages react chemically with the oxygen in the package, they do not prevent external oxygen from penetrating the package. Therefore, it is common in the packaging of such packages to include additional protection such as passive barrier film wraps of the type described above. This adds costs to the product. In view of the disadvantages and limitations of the package or sack, it has been proposed to incorporate an "active" oxygen absorber, that is, one that reacts with oxygen, directly on the walls of a packaging article. As said packaging article is formulated to include a material that reacts with oxygen penetrating through its walls, the package is said to provide "an active barrier" to distinguish it from a passive barrier that only blocks oxygen transmission but does not react with it Active barrier packaging is an attractive way to protect oxygen sensitive products because not only does it prevent oxygen from reaching the product from the outside, it can also absorb oxygen present inside a container wall and absorb the oxygen introduced during filling of the container. An active barrier packaging approach is to incorporate a mixture of an oxidizable metal (eg iron) and an activating component that promotes the reaction of the metal with oxygen, often in the presence of water, in a suitable film-forming polymer. Examples of activating components are electrolytes (for example sodium chloride), acidifying components, electrolytic acidifying components, or halogen compounds hydrolysable in protic solvent, such as Lewis acids (for example aluminum chloride). In the case of nanometals, little or no activating component may be necessary due to its inherent pyrophoricity. The film-forming polymer containing the scavenger is then melt-processed into a monolayer or multilayer article such as a preform, bottle, sheet or film, which ultimately forms the resulting wall or walls containing the oxygen scavenger of the rigid container or flexible or other packaging item. It will be understood that a film-forming polymer is one capable of being converted into a film or sheet. However, the present invention is not limited to films and sheets.

Examples of such film-forming polymers are polyamides, polyethylenes, polypropylenes and polyesters. The container of the present invention also includes bottle walls, trays, container bases or lids. It should be appreciated that references to the side wall of the container and the wall of the container also refer to the top, bottom and upper sides of the container, and a film that can wrap the product such as meat wraps. One difficulty with sweeping systems that incorporate an oxidizable metal or a metal compound and an electrolyte in a thermoplastic layer, is the inefficiency of the oxidation reaction. Frequently a high load of sweeping compositions and relatively large amounts of electrolyte is used to obtain an oxygen absorption rate and a sufficient active barrier packaging capacity. According to U.S. Patent No. 5,744,056, oxygen scavenger compositions exhibiting improved oxygen absorption efficiency with respect to systems such as iand sodium chloride electrolyte, including a non-electrolytic acidifying component in the composition. In the presence of moisture, the combination of the electrolyte and the acidifying component promotes the reactivity of the metal with oxygen to a greater degree than either of them alone. However, when using only the acidifying component, adequate oxygen scavenging properties do not result. A particularly preferred oxygen scavenger composition according to U.S. Patent No. 5,744,013, comprises ipowder, sodium chloride and sodium acid pyrophosphate in approximate amounts of 10 to 150 parts by weight of sodium chloride plus acid pyrophosphate of sodium, per hundred parts by weight of i These conventional sweeping compositions are created by dry mixing the ingredients or depositing the acidifying agents and salts on the metal particle from an aqueous liquid or suspension, and then re-grinding the composition, thus creating more particles. U.S. Patent No. 5,744,056 teaches that the degree of mixing of the oxidizable metal, electrolyte and acidifying components and, if used, the optional binder component, affects the oxygen absorption performance of the oxygen scavenging compositions, with a better mixed producing better performance. The effects of mixing are most noticeable at low proportions of electrolyte + acidifying components, to oxidizable metal component, and at very low and very high proportions of acidifying component to electrolytic component. Below about 10 parts by weight of electrolytic + acidifying components per one hundred parts by weight of metal component, or when the weight ratio of the electrolyte or acidifying component to the other is less than about 10:90, the oxygen scavenging components they are preferably mixed by mixing in aqueous suspension, followed by oven drying and grinding into fine particles. Under these proportions, mixing by suitable techniques at higher speeds, such as mixing the powder with high intensity, such as in a Henschel mixer or a Waring powder mixer, or by lower intensity mixing techniques, as in a container on a roller or rotating drum, can produce variability in the incorporation of oxygen, particularly when the compositions are incorporated into thermoplastic resins and used in melt processing operations. Equally other things, U.S. Patent No. 5,744,056, claims that oxygen scavenger compositions prepared by slurry mixing have the highest efficiency or oxygen absorption performance, followed in order by the compositions prepared using solids blenders. of high intensity and the techniques of mixing in roller / rotating drum. U.S. Patent No. 4, 127,503, teaches the dissolution of an elolyte in water, putting the solution in contact with the oxidizable component (for example iron) and then removing the water from the composition. Although this technique is suitable for salts that dissolve in water, it is not suitable for salts that are hydrolyzed in the presence of a protic solvent such as water. Aluminum chloride, for example, will hydrolyze in the presence of water to form hydrochloric acid and aluminum hydroxide. The incorporation of dry mixtures in the wall of transparent containers is difficult due to the turbidity or color carried by the number of discrete particles. United States Patent Applications No. 20030027912, 20030040564 and 20030108702, teach that the use of larger oxidizable particles minimizes the number of particles and improves the turbidity and color of the transparent wall of the container. As taught by these patent applications, the goal of oxygen scavenger compositions should be to have as few particles as possible. Another deficiency in the use of conventional oxidizable metal compositions mixed or ground dry is the growth of the particle as it is oxidized. It has been observed that as the particle oxidizes, the oxidized material blooms from the particle, making the particle appear larger over time and the color changes to the color of the oxidized metal. In the case of iron, the color of the wall of the container changes to yellow and yellowish orange (rust). The beverage or food containers having the aforementioned efflorescences are commercially unacceptable because the consumer incorrectly attributes the color to the deterioration of the product within the container. The European patent application EP-1 506 718, entitled "Oxygen Scavenging Compositions and Application thereof in Packing Containers", filed on August 14, 2003, and the patent application WO-2005/016 762, entitled "Oxygen-scavenging compositions" and the application thereof in packing and containers ", presented on August 11, 2004, teach that some hydrolysable activating components in protic solvent can be put on the oxidizable component by dissolving the activating component in an organic solution essentially free of moisture, putting in contact the solution with oxidizable metal and then removing the solvent. Although the deposition of the compounds by means of a liquid phase achieves a desired intimate contact for a unit particle, deposition in the liquid phase presents several problems. First, there are the impurities of the solvent or reaction products of the salt with the solvent, often called adducts. These may or may not be linked to the composition. Second, deposition by liquid phase requires a dissolution step and a solvent removal step. A third disadvantage of liquid deposition is that the penetration of the liquid into the pores of many metal particles can be inhibited by the surface tension of the liquid. Yet another deficiency of the liquid deposition is the instability of the liquid composition deposited during the further heat processing of the polymer containing the oxygen scavenger deposited as a liquid. In the case of polyesters, it is advantageous to place the scavenger in the low molecular weight material and then subject the polymer to solid state processing, often at 225 ° C for 16-20 hours. As discussed below, the bottles and preforms made of polymer containing an oxygen scavenger deposited as a liquid became unacceptably yellow with respect to the particles made of this invention. Japanese patent application 09-237232 also describes the deposition of the activating component by means of an aqueous or organic solution and its placement on the wall of a container. The container wall of Japanese publication No. 11-080555 (patent application 09-237232) is a thin sheet metal and plastic laminate containing the oxygen scavenger between the thin sheet and the contents of the package. Thus, the container is not transparent and no advantage is seen in reducing the number of sweeping particles. Reacting the external surface of the iron particle with a compound in a vapor stream is another way to achieve intimate contact. Japanese publication No. 11-302706 (application No. 10-131379), entitled "I Rum Powder For Reactive Material And Its Production" teaches to put a wrapper layer containing 0.1-2% of the weight of chlorine in the powder of iron in the envelope layer which becomes a front face of [sic] ferric chloride by contacting hot chlorine or hydrogen chloride with the iron powder. In this way the ferric chloride forms the front face of said iron powder. Although this reaction of vapor phase - solid phase creates intimate contact, it is limited to the reaction products of iron and various gases. Since the Japanese description requires that the oxidizing agent be a reaction product of the iron, the technician is limited by the kinetics of the iron-based salts and the iron. With this technique, different metals such as aluminum chloride and iron are not available. U.S. Patent No. 6,899,822 teaches the use of an acidifying electrolyte such as sodium bisulfate in the presence of sodium chloride and iron. However, none of the examples teach to deposit the materials on the iron.

BRIEF DESCRIPTION OF THE INVENTION This invention calls for a process for the manufacture of an oxygen scavenging particle, wherein the particle comprises at least one oxidizable component and at least one activating component, and said process comprises contacting the oxidizable component with a gas containing a vapor of the activating component, and depositing the activating component of the gas on the oxidizable component either in liquid or solid form. The invention also discloses that the activating component can contain a halide, in particular a metal halide. In addition, the use of a halogen compound hydrolysable in protic solvent as the activating component is described. Specifically described are AICI3, FeCl2, FeCl3, TiCl4, POCI3, SnCl4, SOCI2, n-butyl-SnCl3, and AIBr3 as halogens hydrolysable in protic solvent. It is also disclosed that the oxidizable component comprises an oxidizable metal or oxidizable metal alloy, preferably iron, aluminum, copper, zinc, manganese, magnesium and cobalt. It is further disclosed that before the deposition of the activating component on the oxidizable component, the oxidizable component can be reduced from a higher oxidation state in a chamber, selected from the group of the same chamber in which the oxidizable component is brought into contact with the activating component, and a camera connected to the chamber in which the oxidizable component is brought into contact with the activating component. Furthermore, a process for the manufacture of an oxygen scavenger particle is described wherein the particle comprises at least one oxidizable component and at least one activating component, and said process comprises contacting the activating component with a gas containing a vapor of the oxidizable component, and depositing the oxidizable component of the gas on the activating component in liquid or solid form. The product of this process can be incorporated in the wall of a container comprising a thermoplastic film-forming polymer, in particular polyethylene terephthalate and polyethylene terephthalate copolymers. Also described is the wall of a container made of film-forming polymers such as a polyamide, polyethylene or polypropylene, wherein the particles are incorporated into the film-forming polymer.

BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 represents a typical vapor deposition apparatus by means of which one component is vaporized in a container called a vaporizer and then deposited on the other component in another container called the deposition reactor.

DETAILED DESCRIPTION OF THE INVENTION The deficiencies of the prior art can be eliminated according to the invention by supplying particles having high oxygen scavenging efficiency in the presence of a protic solvent such as moisture or water in liquid phase. These particles comprise an oxidizable component, preferably an elemental metal such as iron, cobalt, aluminum, copper, zinc, manganese and magnesium, and at least one activating component; wherein one component has been deposited from the vapor phase on the other component. Implicitly, to have then the greatest utility, the two components should not boil or sublimate at standard temperature and pressure. It should be noted that although the examples deal with metals as oxidizable components, the invention is not limited to metals and electrolytes, but to any system where the components meet the criteria described below. The oxidizable component could be an organic compound, so the catalyst has to be deposited from the vapor phase. The function of the activating component is to promote or initiate the reaction of the oxidizable component with oxygen. In the absence of the activating component, there is little or no reaction of the oxidizable component with oxygen. Therefore, the test is to see if the oxidizable component reacts with more oxygen in the presence of the activating component than when the activating component is absent. In the case of an activable system, such as those requiring water, the rate of oxygen consumption of the composition comprising the oxidizable component, the oxidizable component and water, is compared with the oxygen consumption rate of the oxidizable component and water. To give clarity, it is not necessary that the activating component be the true compound that participates in the reaction with oxygen or that catalyzes it, but can participate in a reaction that produces a compound that participates in the reaction with oxygen or catalyzes it. Although not limited to any mechanism, one hypothesis is that aluminum chloride reacts with water to form hydrochloric acid and it is hydrochloric acid that actually establishes the galvanic cell. The other hypothesis is that hydrochloric acid reacts to form iron chloride, which is a known activator of the reaction of oxygen with oxidizable metals. Therefore, it is preferable that the activating component initiates the reaction of the oxidizable component in the presence of water. The phrase "which initiates the reaction of the oxidizable component" means that when it is in the presence of water and the activating component, the oxidizable component becomes more reactive with oxygen than it would be in the presence of water without the activating component. To initiate a particle by water contact, it is essential that this activating component promotes or catalyzes the reaction in the presence of moisture. This promotion can be with or without the production of intermediate compounds. Moisture can come from direct contact with the liquid, absorption of circulating air or steam or migration through another material. The need for water is what makes the composition workable. In a typical application, water will come from packaged items, such as beer or juice. When the composition is attached to the walls of a container, the water from the packaged items migrates to the particle initiating the reaction of the particle with the oxygen that passes from the exterior of the wall to the interior. To be activatable, the activating component must be a water-soluble electrolyte, a water-soluble acidifying electrolyte, a mixture of a water-soluble electrolyte and acidifying agents, or a compound hydrolysable in protic solvent, or must react to form an acidifying electrolyte , a mixture of a water-soluble electrolyte and an acidifying electrolyte. Of the hydrolysable compounds in protic solvent, those having halogens such as chlorine and bromine are preferred. Again, the activating component is a component that increases the reaction rate of the oxidizable component with oxygen. If the activating component remains in the system, it is irrelevant. The ability of the activating component to initiate the oxygen scavenging reaction depends on the acidity and electrolytic forces of the activating component or products of the hydrolysis of the activating component. For example, it is believed that when sufficient water contacts the AICI3 / iron particle, the AICI3 is hydrolyzed to AI2O3 and hydrochloric acid. Hydrochloric acid is a strong acid and electrolyte that promotes the fast and efficient reaction of iron with oxygen. U.S. Patent No. 5,885,481, the teachings of which are incorporated herein by reference, teaches the advantages of using an unhalogenated acidifying electrolytic component. Many hydrolysable compounds in protic solvent, such as titanium tetrachloride, tin tetrachloride and POCI3, SOCI2, SCI2, S2CI2, PCI3, PSCI3, PBr3, POBr3, PSBr3, PCI5, PBr5, SiC4, GeC4, SbCI5, are liquid room temperature and boil quickly. Other compounds hydrolysable in protic solvent, such as AICI3, FeCl2, FeCl3, AIBr3, SbCI3, SbBr3 and ZrCI4, are sublimated at relatively low temperatures. The high-boiling compounds are ZnCl2, ZnBr2 and FeBr3. Preferred halogenated hydrolysable halogenide compounds are halogenides, in particular chloride and bromide, most preferably AICI3, AIBr3, FeCl2, FeBr2, TICI, SnCl4 and POCI3. A non-activatable system can also be made using the vapor deposition process described in this invention. If the activating component is non-activatable, the activating component immediately promotes the reaction of the oxidizable component with oxygen, or with very low amounts of moisture (<70% RH) by contact with the oxidizable component. See, for example, U.S. Patent No. 6,133,361, which discloses metal iodide and metal bromide compounds as examples of activating components that require very little moisture and are therefore non-activatable activating components. Therefore, the metal iodide and metal bromide compounds that can be put into the vapor phase are contemplated by the claims of this process. The vapor deposition process requires two almost unitary operations. The first unit operation or first step is to contact the oxidizable component with the vapor phase of the activating component. The next unit operation or second step is the vapor deposition, wherein the activating component is condensed or de-lubricated as a liquid or solid on the oxidizable component. For clarity, this invention is not limited to the vapor deposition of the activating component on the oxidizable component. The invention is equally applicable to the deposition of the oxidizable component on the activating component if desired. Although the following examples teach and emphasize vapor deposition of the activating component on the oxidizable component, it could be deposited from the vapor stream on the component 7. activator. For example, iron pentacarbonyl, Fe (CO) 5, is thermally decomposed into elemental iron. As it decomposes it moves from the vapor phase. If the thermal decomposition of iron carbonyl were to occur on a bed of sodium chloride particles, elemental iron would form around the sodium chloride particles. In the proper proportions, the water would dissolve the sodium chloride leaving a hollow iron sphere to react with the oxygen in the presence of sodium chloride solution. The contact of the oxidizable component with the activating component in the vapor phase and the condensation or desublimation of the activating component on the oxidizable component are not separate or separate process steps that require intervention or a time interval between them. These unit operations can occur simultaneously. As described in the fourth embodiment, the vapor phase activating component will condense or de-blub when contacted with a cooler oxidizable component. Therefore, the contact step refers to the step of placing the activating component in vapor phase in the same chamber as the oxidizable component, in such a way that the components touch or are in contact. The step of vapor deposition refers to the actual phase change that occurs when the vapor phase activating component goes from a gas to a liquid or to a solid. It will be said that when the hot steam makes contact with the cold solid, the phase change is immediate. Thus, although the steps are mentioned sequentially, it is contemplated that, as shown in the examples, the steps can occur virtually simultaneously. In general, the activating component is placed in a vapor stream by means of boiling, flashing, or sublimation of the activating component, manipulating the temperature and / or pressure. The vaporized activator component is contacted with the oxidizable particles and once in contact with the oxidizable particle, the activating component is deposited from the vapor stream on the oxidizable component by condensation or desublimation. The terms "deposition by means of vapor", "is deposited on", "is deposited from a vapor stream", or "deposition of the component of a gas to a liquid or solid on the oxidizable component", refer to condensation , desublimation or its equivalent, of one component over the other component; usually the deposition of the activating component on the oxidizable component. By implication, even when the word vapor is not present, the deposition occurs by means of a vapor current. The deposition of the activating component on the oxidizable metal by means of a vapor stream intimately binds the activating component with the oxidizable component and creates a discrete particle containing both components. These sweeping particles can then be mixed in a polymer matrix by any of the known techniques, such as dispersion of the particles in the liquid polymer by means of a liquid melting reactor, an extruder, or even during injection or injection molding. extruding an article such as a preform, film or sheet. The vapor deposition can be effected by contacting the activating component in the gas phase with the oxidizable component and condensing the activating component on the oxidizable component. The best results are obtained when the process is carried out taking into account the following observations. The process is best performed in a medium free of oxygen and moisture. Also, due to intimate contact, the required amount of activating component is substantially less than the indications of the prior art. The desired ratio of activating component to oxidizable component can easily be determined by trial and error without further experimentation. The particles are made according to the process, the results are analyzed, and the amount of activating component is increased or decreased to achieve the desired oxygen scavenging activity. The sweep function is not linear with the amount of activating component and at some point too much activating component can be used. The oxidizable component can consist of several compounds or alloys of compounds. Additionally, the activating component is also not limited to a single compound. Additional agents such as binders and water absorbers can be put into the oxidizable particle first, and the particle is subjected to vapor deposition. For example, a suspension in water can be used to put sodium chloride on iron particles, and then to deposit as AICI3 vapor on the NaCl / Fe. Many variations are evident in light of the following modalities. In the first embodiment, the vapor deposition is carried out in a single chamber, placing the desired proportions of oxidizable component and activating component in a chamber or container. The chamber and its contents are then heated to a sufficient temperature and / or exposed to sufficient vacuum to place the activating component in the vapor phase. In the case of aluminum chloride, the activating component is sublimated to the vapor phase. In the case of titanium tetrachloride, the activating component boils to the vapor phase. The pressure should be reduced when using compounds that decompose at high temperatures. The vapor deposition (condensation or desublimation) of the vapor phase activating component on the oxidizable component can be carried out by cooling and / or increasing the pressure, so that the activating component is converted from vapor to a liquid or solid on the oxidizable component. The resulting oxygen scavenger particles can then be incorporated into a polymer matrix which is subsequently transformed into a container wall. In a second embodiment, vapor deposition can be effected by placing the activating component in its gaseous state or vapor phase by heating and / or reducing the pressure surrounding the activating component. The vapor component activating component stream is then contacted with the oxidizable particles. Then, the activating component can be deposited from the vapor stream on the oxidizable particles by cooling and / or increasing the pressure of the system. In a third embodiment, the vapor component activating component stream is contacted with a bed of oxidizable particles. It is advantageous to fluidize the bed and use the gaseous stream of vapor phase activating component as a fluidizing medium. Depending on the amount of activating component, it may be necessary to supplement the vapor stream with an inert gas such as nitrogen to maintain the fluid nature of the bed. Figure 1 depicts the vapor deposition apparatus also used in Examples IV, Vb, Vc and Vd. The vaporizer or sublimator, represented as 1 D, operates as a sublimator of AICI3, represented as 1B. The vaporizer or sublimator, 1 D, is attached to the deposition reactor, represented as 1 F. In Figure 1, nitrogen (N2) is introduced into the vaporizer / sublimator (1 D), through the tube marked as 1C. The nitrogen is heated to the desired sublimation temperature as it passes through the heating medium, preferably a sand bath, represented as 1A. In the case of AICI3, this temperature is approximately 235-250 ° C. For materials that boil instead of sublimate, the temperature would be the respective boiling point or higher. The preheated nitrogen passes through the bed of AICI3, marked as 1 B, fluidizing the AICI3 and carrying the nitrogen vapors / AICI3 through the heated tube marked as U. The heating coils and the insulation of the tube 1 J are represented as E. The nitrogen vapor / AIC is introduced into the deposition reactor marked as 1 F at the base of the fluidized bed of iron represented as 1G, but above the distribution plate identified as 1 K. The iron is fluidized by nitrogen fluidizer introduced into the deposition reactor marked as 1 F through the inlet tube 1 H. The nitrogen flows through holes in the distributor plate 1K. The temperature of the iron particles is substantially lower than the deslimiation or condensation temperature of the AICI3. The cooling of the iron particles causes the AICI3 to condense or desublime from the vapor stream onto the fluidized iron particles. The nitrogen then leaves the deposition reactor at 11. After the AICI3 is consumed and deposited on the iron, the iron is removed from the deposition reactor 1F. The deposition of aluminum chloride on an oxidizable particle, such as elemental iron, is best performed at as fast a rate as possible to minimize the growth of large crystals of aluminum chloride, resulting in a more uniform coating of the particles. For the aluminum / iron chloride system, the sublimator should be operated at a temperature between 225 and 250 ° C, protic solvent at 235-240 ° C and the nitrogen used to sweep the aluminum chloride vapors out of the sublimator should be Preheat approximately at this same temperature. Surprisingly, sublimation of aluminum chloride at a linear nitrogen velocity of 9.3 m / min through a 5 cm diameter sublimator at 250 ° C was slower than sublimation at 235 ° C. It is believed that this is the result of the stacking of aluminum chloride and reduction of the effective surface area from which sublimation can occur. Sublimation can be followed by measuring the temperature of the sublimator at several points along its height. As the aluminum chloride sublimation proceeds, the temperature measured by a probe in the reactor near the top approximates that of the heating bath. With additional sublimation time, a probe near the midpoint will approach this temperature and finally a probe near the base also reaches the temperature of the heating bath. At the same time, the temperature of the metal bed where aluminum chloride condenses will reach a maximum temperature and then, since there is less and less aluminum chloride to sublimate and recondense, it will approach room temperature. Transfer lines must be drawn for the vapor deposition reactor to prevent the vaporized component condensing in the line. In the case of aluminum chloride, the temperature of the line should be maintained at at least 200 ° C, preferably at about 220 ° C, to avoid condensation of the aluminum chloride in the lines. The speed of the nitrogen through the fluidization reactor depends on the shape and size of the powder of the oxidizable particles and also on the design of the reactor. This must be determined experimentally. An agitator was also conditioned in the reactor to provide the most efficient mixing of the oxidizable particles and consequently to optimize the uniformity of the vapor deposition. The operation of a bed of particles is well known and said bed can be fluidized, fixed, horizontal or vertical. The bed can be movable, as in a continuous operation, or static, where the steam is recirculated through of the bed until the desired amount of activating component is deposited on the oxidizable component. The deposition may comprise its own series of variations. In the fourth preferred embodiment the stream of vaporized activator component is contacted with a bed of cooler oxidizable particles. The temperatures of the activating component and the oxidizable component are selected in such a way that once the vapor stream makes contact with the oxidizable component, the activating component is immediately deposited from the vapor stream on the cooler oxidizable component. An alternative variation is to pass the coolest oxidizable component through the chamber containing the vaporized activator component. The person skilled in the art will recognize that a simple enthalpy balance will determine the maximum allowable temperature of the solid oxidizable component. The chosen temperature must be lower than the respective vaporization temperature of the activating component at the deposition pressure, usually atmospheric. The following example demonstrates that mathematics is applied to oxidizable metal. Therefore, the initial temperature must be less than the vaporization temperature at the deposition pressure minus the amount of activating component by the heat of vaporization of the activating component divided by the product of the amount of oxidizable metal by the heat capacity of the metal solid. [(Tv - Ts) x CpACg + Hv)] x AC <; (Tf - Ti) x (OC x Cpocs) where: Tv = temperature of the activating component in its initial vapor phase Ts = temperature at which the activating component desublimates or condenses Cpocs = Caloric capacity of the oxidizable component at the conditions of the deposition Hv = heat of desublimation or condensation of the activating component at the deposition temperature and pressure AC = quantity of the activating component Ti = initial temperature of the oxidizable component Tf = final temperature of the oxidizable component OC = quantity of oxidizable component Cpocs = caloric capacity of the oxidizable component to deposition conditions.

The maximum initial temperature will occur if the final temperature of the oxidizable component reaches the deposition temperature (sublimation or boiling point). Therefore, Ts can be replaced by Tf and the rest can be resolved for the maximum Ti. Therefore, Ti can be smaller than the value in the following equation. You < Ts - [((Tv - Ts) x CpACg + Hv)) x AC / (OC x Cp0Cs)] In practice you want to keep the initial temperature well below the vaporization temperature. After dispersion in the polymer matrix of the vapor deposited oxygen scavenger particle, each recess or polymer capsule containing a particle with the oxidizable component will also contain an activating component. In contrast, when a dry mixture of the activating and oxidizable components is incorporated into the polymer matrix, often the separated particles are not in the same vicinity and the polymer that separates the activating component from the oxidizable component creates a barrier, which makes the particle virtually ineffective as an oxygen scavenger. Preferably the oxidizable particles have an average particle size of less than 50 μm. Based on cost, iron is the preferred metal. Although electrolytically annealed or non-annealed reduced iron is preferred, reduced sponge irons with carbon monoxide or hydrogen are also suitable. It should be noted that reduced forms with hydrogen and carbon monoxide, known as sponge iron, are generally less reactive than electrolytically reduced iron. Although iron is the preferred oxidizable component for cost reasons, cobalt, tin, aluminum, zinc, manganese and copper are candidates for the process of the invention. It is also possible to reduce the oxidizable component immediately before vapor deposition, thus creating an efficient batch or continuous production process starting with cheap oxidized raw materials. For example, the reduction of iron oxide to elemental iron is well known and can be done by passing hydrogen or hot carbon monoxide over the metal. Hydrogen or carbon monoxide reacts with oxygen leaving the reduced porous metal. In a batch process, the reduction would occur in the same chamber as the deposition. In a continuous process, the reaction would occur in a separate chamber and the reduced metal would pass to a different chamber where the activating component would be deposited on the oxidizable metal. Vapor deposition as used in this invention is also very efficient when creating nanoscale oxygen scavenging particles compared to conventional suspension mixing or contacting techniques. Iron nanoparticles are those particles with diameters less than 1 miera, preferably less than 500 nanometers, and most preferably less than 200 nanometers. The intimate contact of the activating component is essential for the nanoparticles in a fixed medium such as a film or container wall. Dry blends of traditional sweeping compositions do not provide sufficient activating component in intimate contact with the nanofiller to be efficient in a fixed environment. The addition of the reduction step before the vapor deposition is particularly useful in the nanofiller treatment. Due to this pyrophoricity, often the nanofierro is treated with oils or organic solvents in such a way that it can be handled and dispatched safely. These solvents frequently reduce the reactivity of the nanofierro. However, fully oxidized iron (nano-rust) is readily available at the nanoscale and is used for pigments and paints. This nano-rust can be placed in a reduction chamber and reduced to nanofierro. Then the nanofierro can be transported to the vapor deposition chamber where the vaporized activating component is deposited from the steam stream on the nanofierro. In this way, the nanoscale oxygen scavenger can be done in a batch or continuous process starting with nano-rust. In another embodiment, the nano-rust can be reduced in the same chamber of vapor deposition. It is not necessary that the oxidizable component, particularly metals, be 100% pure. Minor alloy elements such as nickel, chromium, silicon and other compounds may be present. Using iron as an example, mixtures of iron with minor amounts of other metals can be used. The iron-based compositions are incorporated into the wall of a container made of film-forming polymers, preferably aromatic polyester, in amounts of 500 to 10000 parts by weight per million parts by weight of polymer, preferably from 1,000 to 6000 parts per million. of polymer parts. In the case of nanoscale sweepers 200-2000 ppm may be sufficient. When used in non-transparent packaging, the amounts of sweeping composition can be as high as 5 percent by weight of the total polymer-iron composition. Of the film-forming polymers, polyester is preferred. Suitable polyesters include those produced from aromatic, aliphatic or cycloaliphatic dicarboxylic acids of 4 to about 40 carbon atoms and aliphatic or alicyclic glycols having from 2 to about 24 carbon atoms. The polyesters employed in the present invention can be prepared by well-known conventional polymerization methods. Polyester polymers and copolymers can be prepared for example by melt phase polymerization which includes the reaction of a diol with a dicarboxylic acid or its corresponding diester. Various copolymers produced from diols and multiple diacids can also be used. Polymers containing repeating units of only one chemical composition are homopolymers. Polymers with two or more chemically different repeat units in the same macromolecule are called copolymers. The diversity of the repeated units depends on the number of different types of monomers present in the initial polymerization reaction. In the case of polyesters, the copolymers include the reaction of one or more diols with a diacid or multiple diacids, and are sometimes referred to as terpolymers. As indicated above, suitable dicarboxylic acids include those comprising from about 4 to about 40 carbon atoms. Suitable dicarboxylic acids include, without limitation, terephthalic acid, isophthalic acid, naphthalene-2,6-dicarboxylic acid, cyclohexanedicarboxylic acid, cyclohexanediacetic acid, diphenyl-4,4'-dicarboxylic acid, 1,3-phenylenedioxydiacetic acid, acid 1, 2-phenylenedioxydiacetic acid, 1,4-phenylenedioxydiacetic acid, succinic acid, glutaric acid, adipic acid, azelaic acid, sebacic acid, and the like. Specific esters include, without limitation, the various isomeric italic and naphthalic diesters. These acids or esters can be reacted with an aliphatic diol preferably having from about 2 to about 4 carbon atoms, a cycloaliphatic diol having from about 7 to about 24 carbon atoms, an aromatic diol having from about 6 to about 24 carbon atoms, or an ether glycol having 4 to 24 carbon atoms. Suitable diols include, without limitation, ethylene glycol, 1,4-butenediol, trimethylene glycol, 1,6-hexanediol, 1,4-cyclohexanedimethanol, diethylene glycol, ethyl ether of ethoxy resorcinol, and ethyl ether of ethoxy hydroquinone.

Polyfunctional comonomers can also be used, usually in amounts of about 0.1 to about 3 mole percent. Suitable comonomers include, without limitation, trimellitic anhydride, trimethylolpropane, pyromellitic dianhydride (PMDA), and pentaerythritol. Polyester-forming polyacids or polyols can also be used. Mixtures of polyesters and copolyesters may also be useful in the present invention. A preferred polyester is polyethylene terephthalate (PET) formed from the approximate 1: 1 stoichiometric reaction of terephthalic acid, or its ester, with ethylene glycol. Another preferred polyester is polyethylene naphthalate (PEN) formed from the approximate 1: 1 to 1: 1.6 stoichiometric reaction of naphthalenedicarboxylic acid, or its ester, with ethylene glycol. Another preferred polyester is polybutylene terephthalate (PBT). Also preferred are PET copolymers, PEN copolymers and PBT copolymers. The specific copolymers and terpolymers of interest are PET with combinations of isophthalic acid or its diester, 2,6-naphthalic acid or its diester, and / or cyclohexanedimethanol. The esterification or polycondensation reaction of the carboxylic acid or ester with glycol normally occurs in the presence of a catalyst. Suitable catalysts include, without limitation, antimony oxide, antimony triacetate, antimony ethylene glycollate, organomagnesium, tin oxide, titanium alkoxides, dibutyltin dilaurate, and germanium oxide. These catalysts can be used in combination with zinc, manganese or magnesium acetates or benzoates. Catalysts comprising antimony are preferred. Another preferred polyester is polytrimethylene terephthalate (PTT). It can be prepared, for example, by reacting 1, 3-propanediol with at least one aromatic diacid or alkyl ester thereof. Preferred diacids and alkyl esters include terephthalic acid (TPA) or dimethyl terephthalate (DMT). Accordingly, the PTT preferably comprises at least about 80 mole percent of TPA or DMT. Other diols which can be copolymerized in said polyester include, for example, ethylene glycol, diethylene glycol, 1,4-cyclohexanedimethanol, and 1,4-butanediol. Isophthalic acid and sebacic acid are an example of the simultaneous use of an aromatic and aliphatic acid to make a copolymer. Preferred catalysts for preparing PTT include titanium and zirconium compounds. Suitable titanium catalyst compounds include, without limitation, titanium alkylates and their derivatives, complex titanium salts, titanium complexes with hydroxycarboxylic acids, coprecipitates of titanium dioxide-silicon dioxide, and alkali metal hydrated titanium dioxide. Specific examples include tetra- (2-ethylhexyl) -titanate, tetra-stearyl titanate, d, -propoxy-bis (acetyl-acetonate) -titanium, d-n-butoxy-bis (triethanolamine) -titanium, tributyl monoacetyltitanate, triisopropyl- monoacetylititanate, tetrabenzoic acid titanate, alkali titanium oxalates and malonates, potassium hexafluorotitanate, and titanium complexes with tartaric acid, citric acid or lactic acid. The preferred catalytic titanium compounds are titanium tetrabutylate and titanium tetraisopropylate.

The corresponding zirconium compounds can also be used. The polymer that is used in this invention may also contain small amounts of phosphorus compounds such as phosphates, and a catalyst such as a cobalt compound, which have to impart a blue tone. Small amounts of other polymers such as polyolefins can also be tolerated in the continuous matrix. The melt phase polymerization described above can be followed by a crystallization step, then a solid phase polymerization step (SSP) to obtain the intrinsic viscosity necessary for the manufacture of some articles such as bottles. The crystallization and polymerization can be carried out in a rotary drum dryer reaction in a batch system. In many cases it is advantageous to incorporate the scavenger immediately after the polymerization step in the melting phase and subject the polymer containing the scavenger to the solid phase polymerization. The vapor deposition process of this invention creates particles that substantially do not degrade or color the polymer during solid phase polymerization. By contrast, the product of the organic liquid deposition process does cause discoloration. It is believed that this comes from the organic trap or adducts that bind to the particle. Alternatively, the crystallization and polymerization can be carried out in a continuous solid state process by means of which the polymer flows from one container to another after its predetermined treatment in each container. The crystallization conditions preferably include a temperature from about 100 ° C to about 150 ° C. The solid phase polymerization conditions preferably include a temperature from about 200 ° C to about 232 ° C, preferably from about 215 ° C to about 232 ° C. The solid phase polymerization can be carried out for a sufficient time to raise the intrinsic viscosity to the desired value, which will depend on the application. For a typical bottle application, the preferred intrinsic viscosity is from about 0.65 to about 1.0 deciliter / gram, determined according to ASTM D-4603-86 at 30 ° C in a 60/40 by weight mixture of phenol and tetrachloroethane. The time required to reach this viscosity can vary from about 8 to about 21 hours. However, a film-forming polyester of at least 0.45 dl / g, one v.i. of intermediate load of 0.49 to 0.59 dl / g, or of _ > preference of 0.52 to 0.56 dl / g. The polymer could also be one. polyester resin for bottle v.i. of loading from 0.59 to 0.69 dl / g, preferably from 0.61 to 0.64 dl / g, with a v.i. typical for bottles from 0.72 to 0.84 dl / g, preferably from 0.74 to 0.82 dl / g. For tray packing the v.i. typical varies from 0.80 to 1.50 dl / g, preferably from 0.89 to 0.95 dl / g. It is noteworthy that although the v.i. The measure of a polymer is a single value, the value represents the combination of the various chain lengths of the molecule. In one embodiment of the invention, the article-forming polymer of the present invention may comprise recycled polyester or recycled polyester-derived materials, such as polyester monomers, catalysts and oligomers. Examples of other film-forming polymers include polyamides, polycarbonate, PVC and polyolefins such as polyethylene and polypropylene. The oxygen scavenger compositions can be added directly into the thermoplastic polymer composition or the melt manufacturing operation, such as the extrusion section thereof, after which the molten mixture can advance directly to the manufacturing line from the article. Alternatively, the compositions can be compounded into concentrated masterbatch pellets, which are then incorporated into the packaging polymers for further processing in the desired article. The concentrates in the polyester resins preferably contain more than 20 parts of oxygen scavenging composition per one hundred parts of resin, preferably between 5 and 10 parts per hundred. Containers having at least one wall incorporating the oxygen scavengers of the present invention are the preferred articles. Cups, bags, boxes, bottles, covers and wrapping films are also examples of such walls. Stretched and unstretched films are included in the container definition. It is also contemplated to provide articles with both active and passive oxygen barrier properties using one or more passive gas barrier layers in conjunction with one or more layers according to the invention. Alternatively, the passive barrier and the oxygen scavenging composition may be in the same layer. Thus, for products that require prolonged shelf life, an oxygen scavenger layer according to the present invention can be used in conjunction with a passive gas barrier layer. Another advantage of the claimed particles and of the manufactured polymers and articles in which they are incorporated, is their stability in storage, that is, they lack reactivity in the absence of moisture, which allows for long periods of storage before filling. As mentioned, containers having at least one light transmitting wall comprising the oxygen scavenger compositions of the present invention advantageously possess high scanning efficiency and the unique property of reduced efflorescence of the particle by reaction with oxygen in the presence of moisture. The reduced efflorescence size also occurs in containers that have turbidity values within a commercially acceptable scale. Many polymers are transparent, but polymers that are transparent to visible light can be made opaque as a result of the presence of additives such as fillers, sweepers, stabilizers and similar additives. Opacity originates from the scattering of light that occurs within the material. Turbidity is the measure of the amount of light deviation from the direction of transmittance by at least 2.5 degrees. The color and gloss of a polymer article can be observed with the naked eye and can also be determined quantitatively by HunterLab ColorQuest spectrometer. This instrument uses the designation CIÉ 1976, a *, b * and L * of color and brightness. A coordinate a * defines a color axis where positive values are towards the red end of the color spectrum and negative values are towards the green end. The b * coordinate defines a second color axis, where the positive values are towards the yellow end and the negative values are towards the blue end. Higher L * values indicate higher material brightness. As indicated, containers comprising at least one wall incorporating the oxygen scavengers of the present invention do not exhibit aging as great as conventional sweepers by aging. The microscopic observation of the wall after aging shows a limited number of black spots evenly distributed within the wall; the wall area occupied by the points is a small fraction of the total area. In contrast, the wall of the containers incorporating oxygen scavengers of the prior art shows remarkable spots due to the formation of large efflorescences distributed along the wall. Conventional sweepers also show a yellow / orange coloration. The compositions indicated in the examples showed a darkening of the container wall, but no yellow / orange color change. The color parameters of the wall of the containers of the present invention show a small reduction of the a * negative values and the positive b * values, with respect to the values of a * and b * of the wall that does not contain sweepers, while that the walls incorporating the prior art sweepers show a * positive values and higher positive b * values. Preferred wall containers are drawn bottles with a thickness of about 280 to 410 μm and turbidity values of about 1% or less per 25.4 microns thick. It is to be noted that all the side walls of the bottle used in the examples are of the indicated thicknesses. The following examples are provided for the purpose of illustrating the manufacture of the composition and the properties of the composition, and are not considered to be limiting of the scope of the invention. Although the preferred embodiment of the invention has been described in accordance with the patent statutes, the scope of this invention is not limited thereto, but is defined by the appended claims. In this way, the scope of the invention includes all modifications and variations that may be within the scope of the claims.

Standard evaluation procedure The oxygen scavenging of each series of sweeping particles and the aesthetics of the bottle were evaluated, as follows: Unless otherwise indicated, the sweeping particles were dispersed in the polymer matrix of preforms of 52 or 27 grams by mixing 6 g of the oxygen scavenger particles with 1994 g of a commercially available PET copolyester (8006S provided by M &G Polymers USA, LLC) which had previously been dried overnight in a 150 vacuum oven ° C in a can. The physical mixture was then charged to an injection molding machine that melted the polymer and dispersed the particles in the preforms. The preforms were blown in bottles of 2 liters or 600 ml, respectively, after a one-day aging. In the case of sweeping nanoparticles, 1000 ppm of the sweeping particles were added to the polymer. Panels were cut from the walls of the bottles and the oxygen scavenging capacity was analyzed using the accelerated oxygen scavenging test method described in the methods section. The oxygen data are indicated in table I and show the high degree of sweeping and activable nature of the sweeper. Table II indicates the aesthetics of the bottle in terms of turbidity, L *, a * and b *.

EXAMPLE I Fe0 / 10% FeCl3 in sealed container A 50 ml Erlenmeyer flask with a screw cap was dried at 150 ° C under nitrogen (nitrogen) and cooled to room temperature. The flask was then charged with the activating component (5.42 g or 0.033 mol of anhydrous FeCI3 obtained from Aldrich Chemical Company) and 55.8 g (1.0 mol) of oxidizable component (reduced iron powder of American Hoganas, grade XCS 50). The FeCl 3 (boiling point of 316 ° C, vaporization temperature of 300 ° C) was converted to a gas and brought into contact with reduced iron by placing the capped flask in a fluidized sand bath at 300 ° C overnight. The FeCl3 was deposited on the iron by cooling the flask under nitrogen. The resulting particles were crumbled and ground to obtain finer particles. The oxygen scavenging particles contained 3.28 weight percent chloride. The oxygen scavenging analysis showed that there was little reactivity under dry conditions but a high degree of reactivity in humid conditions. This indicated that the system was highly reactive and also activatable.

EXAMPLE II Fe0 / FeCl in a fluidized bed A tubular fluidized bed deposition reactor was charged with 5.45 kg of electrolytically reduced iron metal powder of -38 / + 20 microns in size (EA-230 grade, available from OMG, now North American Hoganas). The sieve cut -38 / + 20 was obtained by sifting the powder through Tyler sieves of 38 micras and 20 micras and recovering the part on the sieve of 20 micras. The iron powder bed was fluidized by passing nitrogen at a sufficient rate through a nitrogen distributor plate and through the bed. FeCl3 (Aldrich, USA) was vaporized in the gas phase in a second reaction vessel called a vaporizer or sublimator. 26 g of FeCl 3 (nominally 0.5% w / w of FeCl 3) were placed in the steamer which was enclosed in a sand bath at 300 ° C. The FeCl3 was taken to the fluidized bed by passing nitrogen over the FeCl3, taking the nitrogen containing the FeCl3 vapors from the upper part of the reactor and leading it through a traced, isolated transfer line to the tubular fluidized bed reactor containing the Fluidized metal powder. The vaporized FeCl 3 was contacted with the iron by introducing the FeCl 3 just above the nitrogen distribution plate of the tubular reactor. After the FeCl3 in the vaporizer reached 300 ° C, the temperature of the sand bath was increased to 340 ° C for 1 h. During the next two hours the vaporizer was kept at 340 ° C; in those two hours the temperature of the iron increased to 56 ° C. This increase in iron temperature indicates the deposition of FeCl3 on the colder iron, due to the latent heat of vaporization released during the change of phase from vapor to solid. After two hours the supply of heat and nitrogen fed to the vaporizer was closed; the fluidized iron was then cooled to less than 45 ° C and discharged. When the vaporizer was opened it was seen that 1 g of an orange-red solid remained (presumably Fe203). Again, the reactivity is very high, particularly if it is considered that there was only 0.5% w / w of FeCl3, unlike the example I where there was nominally 10% w / w of FeCl3.

EXAMPLE III Fe0 / AICI3 in a sealed container A 50 ml Erlenmeyer flask with a screw cap was dried at 150 ° C and cooled to room temperature. 2.5 g (0.019 mol) of anhydrous AICI3 (Aldrich, sublimation temperature 178 ° C) and 100 g (1.8 mol) of reduced iron powder of -20 microns were placed in the flask. The -20 micron powder was obtained by screening EA-230 electrolytically reduced iron metal powder (available from OMG, now North American Hoganas). The flask containing the AICI3 and iron was capped and stirred to mix the ingredients. The AICI3 was vaporized and put in contact with the iron by placing the flask in a fluidized sand bath at 175 ° C for 3 hours, removing the flask every 30-60 minutes to crumble the weakly agglomerated mass. The AICI3 was deposited on the iron by cooling the flask to room temperature under nitrogen. The resulting particles were crumbled and ground. The analysis showed a total of 2.02% chloride on the particles. In this evaluation 4 g of particles were dispersed in 1996 g of copolyester, and the resulting bottle was a panel bottle formed by heat. Bottles were also made with 2000 ppm of the particles and 5% nylon MXD6 6001 from Mitsubishi Gas Chemical. In these bottles an accelerated oxygen test was not done.

EXAMPLE IV Fe0 / 5% of AICU in a fluidized bed The tubular fluidized bed reactor of Example II was charged with 5.45 kg of electrolytic iron powder EA-230 (available from OMG, now North American Hoganas, USA) was sieved at -20 microns. The vaporizer of Example II contained 272.6 g of AICI3 (Aldrich, USA) and was placed in a sand bath at 225 ° C. Unlike Example II, hot nitrogen was passed through the AICI3 gas, taken from the top of the vaporizer and conducted through an isolated transfer line drawn to the tubular fluidized bed reactor containing the fluidized iron. The gaseous stream of AICI3 was contacted with the iron by introducing the gas into the tubular reactor above the nitrogen distributor plate. The process was carried out for 15 minutes after which the temperature immediately above the distributor plate in the vaporizer reached that of the top of the vaporizer. The deposition of AICI3 on the iron was evident since the temperature of the iron increased to 57 ° C. Then the supply of heat and nitrogen fed to the vaporizer was shut off and the materials in the fluidized bed began to cool. When the iron cooled to less than 45 ° C it was discharged. When the vaporizer was opened practically no AICI3 was seen. In addition, no evidence of AICI3 was observed in the upper part of the reactor containing the iron.

EXAMPLE Goes Nano-Fe ° "230 nm" / 2% AIC in a fluidized bed The reduction of the nanofierro was made placing 3.1 kg of ferric oxide (R 1299, which measured 230 nanometers in diameter before the reduction, available from Elementis Pigments, East San Luis, Illinois, USA) in the tubular fluidized bed reactor of example II. The reactor was placed in a sand bath and heated while passing nitrogen at the base of the reactor at a sufficient rate to fluidize the bed. When the reactor reached a temperature of 450 ° C, the gas flow was changed from nitrogen to hydrogen. The hydrogen was passed through the reactor for 1 h, maintaining the temperature at approximately 500-510 ° C. Then the hydrogen was replaced with nitrogen and the reactor was removed from the sand bath and allowed to cool overnight without opening. 43 g of AICI3 (Aldrich) was placed in the vaporizer of Example II and in a sand bath at 225 ° C. Hot nitrogen was passed over the top of the AICI3, brought to the top of the reactor, was conducted through an isolated transfer line drawn to the tubular reactor containing the fluidized reduced nanofier. The AICI3 was contacted with the iron by introducing the AICI3 into the tubular reactor at a point above the nitrogen distributor plate. The temperature of the iron increased, indicating the deposition of AICI3. the process continued for 30 minutes after the vaporizer temperature reached that of the sand bath. Then the supply of heat and nitrogen fed to the vaporizer was closed and the iron was cooled to less than 45 ° C. The product was covered with approximately 500 ml of mineral oil and discharged. When the vaporizer was opened, a remnant of 11 g of AICI3 was seen.

EXAMPLE Vb Nano-Fe ° "10x100 nm" / 10% AICI ,. in a fluidized bed 1.95 kg of ferric oxide (AC-1022 from Johnson Matthey, Jacksonville Florida, USA) was reduced in the same manner as in Example Va. Aluminum chloride (AICI3; Aldrich, 136 g) was vaporized by passing hot nitrogen through the bed of AICI3 which was contained in a tubular reactor immersed in a sand bath at 225 ° C. The AICI3 containing the nitrogen was then taken from the upper part of the reactor and brought into contact with the iron by introducing the AICI3 into the tubular reactor containing the iron, at a point above the nitrogen distributor plate. The temperature of the iron increased, indicating the deposition of AICI3. The process continued for 30 minutes after the temperature in the vaporizer reached that of the sand bath. Then the supply of heat and nitrogen fed to the vaporizer was closed and the iron was cooled to less than 45 ° C. The product was pyrophoric, so that two 240 ml beakers were filled with dry powder under nitrogen and sealed. Degassed mineral liquor (1.5 I) was added and the resulting suspension was discarded. Practically no AICI3 was observed in the vaporizer.

EXAMPLE Vc Nano-Fe ° "10x100 nm" / 20% AICl3 in a fluidized bed The process of Example Vb was repeated using 272 g of AICI3. The product was not pyrophoric but was treated as in example Vb as a precaution.

EXAMPLE Vd Nano-Fe ° "80 nm" / 10% AICU in a fluidized bed 1.96 kg of ferric oxide (ColorTherm Red 110M from Bayer) was reduced, as described in Example Va. Then 136 g of AICl3 (Aldrich) was vapor deposited on the ColorTherm Red 110M in the same manner described in Vb.

EXAMPLE Via Comparison of Fe ° / Mixed AICI Under a nitrogen atmosphere, aluminum chloride powder was added directly to electrolytic iron powder, at 2.5% and 10% by weight, based on the weight of the iron, and mixed for two hours at room temperature in a roller mill . These mixtures were labeled Via and Vib, respectively. 2 liter bottles were made and the properties of the side walls were measured. Hunter's turbidity for the 10% to 3000 ppm iron mixture was 53%, well above any commercially acceptable criteria for a clear bottle.

EXAMPLE Vlc Comparison A dry mix of 3000 ppm by weight of Freshblend ™ Scavenger iron from Multisorb Technologies, Buffalo, New York, USA. UU It was injection molded with PET into a 52.5 g preform and turned into a bottle (see "Multiple Functionality Sorbents", Calvo, William D. "Proceedings of ACTIVEPack Conference", page 9 (2003) (announcing the commercialization of Freshblend ™ for polyester) The side wall was subjected to the accelerated oxygen absorption test (0.11 cm3 of 02 μg of polymer / 1000 ppm of Fe) Although the compositions had comparable oxygen absorption, the size of the efflorescence is significantly lower for example I, the subject of the present invention.

EXAMPLES Vine and Vle Other mix comparisons Compositions were made by mixing iron and NaCl (8% w / w based on the weight of iron) and mixing iron and NaHS04 (10% w / w based on iron weight, as described in U.S. Patent No. 5,885,481 ). These mixtures were prepared by directly adding the appropriate salt to the iron powder and then mechanically mixing the mixture in a rotary mill. These two compositions were labeled as Vid and Vle respectively and were converted into 2 liter bottles containing 4000 ppm of any of the mixtures.

EXAMPLES V Convenience of solid state polymerization This series shows the improvement of the vapor deposition on the deposition of an organic solution. The vapor deposition material (Vlla against Vllb) does not exhibit the color change exhibited by the deposited organic sweeper (Vllc versus Vlld), in particular after heat treatment as in the solid phase polymerization. Vlla and Vllb were blown into 0.5 liter bottles, while Vllc and Vlld were blown into 2 liter bottles. Thus, the comparison is the change of color within the same bottle. The example Vlla is the bottle of example IV. It is brought here separately to give clarity to the comparison. In Example Vllb, 3000 ppm of the iron of Example IV was combined by means of a double worm extruder with the loading resin (nominal intrinsic viscosity of 0.49) of Cleartuf® 8006S available from M & amp;; G Polymers, USA UU The filler resin was then crystallized and polymerized in its solid phase under vacuum until the v.i. it reached 0.84. Then, the material was blown into bottles using the methods described above.

In the Vllc example, bottles were made using 3000 ppm of scavenger prepared by depositing the AICI3 of an organic solution on iron as taught in example 1 of European patent application 03425549.7, entitled "Oxygen Scavenging Compositions and the Application thereof in Packaging Containers ", filed on August 14, 2003, which is incorporated herein by reference. In the example Vlld, 3000 ppm of scavenger of Example Vllc were combined with polymerized polyester in solid phase and transformed into bottles in a similar manner to Example Vllb.

TABLE l Performance of oxygen scavenging TABLE I (Continued) TABLE II Bottle data Analytical Procedures Accelerated Oxygen Absorption Test - Polymer Samples Bottle side wall samples of the iron-containing compositions are cut to a predetermined size with a mold and the weights of the side wall samples are recorded to the nearest hundredth of a gram . The samples are placed in 20 ml gas chromatography flasks. The bottles are analyzed dry or with activation. The activated (wet) samples are activated by placing 2 ml of 0.001 M aqueous acetic acid in the vial before sealing. The side wall samples are stored at 50 ° C. The individual bottles are analyzed by gas chromatography to determine the oxygen consumption compared to a control at the preset time interval. Intrinsic Viscosity The intrinsic viscosity of poly (ethylene terephthalate) of intermediate molecular weight and low crystallinity and related polymers that are soluble in phenol / tetrachloroethane 60/40, was determined by dissolving 0.1 g of the ground polymer or pellet in 25 ml of phenol solution / 60/40 tetrachloroethane and determining the viscosity of the solution at 30 ° C +/- 0.05, with respect to the solvent at the same temperature using an Ubbelohde 1B viscometer. The intrinsic viscosity is calculated using the Billmeyer equation based on the relative viscosity. The intrinsic viscosity of poly (ethylene terephthalate) of high molecular weight and highly crystalline and related polymers that are not soluble in phenol / tetrachloroethane, was determined by dissolving 0.1 g of the ground polymer or pellet in 25 ml of trifluoroacetic acid / dichloromethane and determining the viscosity of the solution at 30 ° C +/- 0.05, with respect to the solvent at the same temperature using an Ubbelohde viscometer of OC type. The intrinsic viscosity is calculated using the Billmeyer equation and converted, using a linear regression, to obtain results that are consistent with those obtained using phenol / tetrachloroethane solvent. The linear regression is: v.i. in phenol / tetrachloroethane 60/40 = 0.8229 x v.i. in trifluoroacetic acid / dichloromethane + 0.0124 Measurement of Hunter turbidity Measurements were taken through the side walls of the bottle. A HunterLab Color QUEST Sphere spectrophotometer system equipped with a IBM PS / 2 model 50Z computer, IBM Proprinter II dot matrix printer, graded specimen retainers, and green, gray and white calibration tiles, and light trap was used. The integrating sphere sensor of the HunterLab spectrocolorimeter is a color and appearance measuring instrument. The light of the lamp is diffused by the integrating sphere and passes (transmission) through an object, or is reflected (reflectance) by it, towards a lens. The lens picks up the light and directs it to a diffraction grating that disperses it into its component wavelengths. The scattered light is reflected on a silicon diode array. The signals from the diodes pass through an amplifier to a converter and are manipulated to produce the data. The software produces the turbidity data. It is the calculated ratio of the diffuse light transmittance to the total light transmittance, multiplied by 100, to produce a "% turbidity" (0% being a transparent material and 100% an opaque material). Samples prepared for transmittance or reflectance should be clean and free of any scratches or surface abrasions. The size of the sample must be consistent with the geometry of the aperture of the sphere, and in the case of transmittance, the size of the sample is limited by the dimension of the compartment. Each sample is tested in four different places, for example on the side wall of the bottle or representative film area.

A Panametrics Magna-Mike 8000 Hall Effect Thickness Gauge was used to measure the thickness of the side wall of the bottle.

Claims (77)

1. NOVELTY OF THE INVENTION CLAIMS 1. - A method for manufacturing an oxygen scavenging particle wherein the particle comprises at least one oxidizable component and at least one activating component, and said method comprises contacting the oxidizable component with a gas containing a vapor of the activating component, and depositing the activating component of the gas on the oxidizable component in a liquid or solid form. 2. The process according to claim 1, further characterized in that the activating component contains a halogenide. 3. The process according to claim 1, further characterized in that the activating component is a metal halide. 4. The process according to claim 1, further characterized in that the activating component is a halogen compound hydrolysable in protic solvent. 5. The method according to claim 1, further characterized in that the activating component comprises at least one compound selected from the group consisting of AICI3, FeCl2, FeCl3, TiCl4, POCI3, SnCl4, SOCI2, n-butyl-SnCl3, and AlBr3 6. - The method according to claim 1, further characterized in that the activating component comprises at least one compound selected from the group consisting of AIBr3, AICI3, FeCI2 and FeCI3. 7. The method according to claim 1, further characterized in that the activating component comprises at least one compound selected from the group consisting of AICI3 and AIBr3. 8. The method according to claim 1, further characterized in that the activating component comprises at least one compound selected from the group consisting of FeCI2 and FeC. 9. The process according to claim 1, further characterized in that the oxidizable component comprises at least one compound selected from the group consisting of an oxidizable metal and oxidizable metal alloy. 10. The process according to claim 1, further characterized in that the oxidizable component comprises an oxidizable metal selected from the group consisting of iron, aluminum, copper, zinc, manganese and magnesium. 11. The process according to claim 10, further characterized in that the activating component contains a halogenide. 12. The process according to claim 10, further characterized in that the activating component is a metal halide. 13. The process according to claim 10, further characterized in that the activating component is a halogen compound hydrolysable in protic solvent. 14. The process according to claim 10, further characterized in that the activating component comprises at least one compound selected from the group consisting of AICI3, FeCl2, FeCl3, TiCl4, POCI3, SnCl4, SOCI2, n-butyl-SnCl3 and AIBr3. 15. The process according to claim 10, further characterized in that the activating component comprises at least one compound selected from the group consisting of AIBr3, AICI3, FeCI2 and FeCI3. 16. The process according to claim 10, further characterized in that the activating component comprises at least one compound selected from the group consisting of AICI3 and AIBr3. 17. The process according to claim 10, further characterized in that the activating component consists of FeCI2 and FeCI3. 18. The method according to claim 10, further characterized in that the oxidizable component comprises iron. 19. The process according to claim 18, further characterized in that the activating component contains a halide. 20. The process according to claim 18, further characterized in that the activating component is a metal halide. 21. The method according to claim 18, further characterized in that the activating component is a halogen compound hydrolysable in protic solvent. 22. The process according to claim 18, further characterized in that the activating component comprises at least one compound selected from the group consisting of AICI3, FeCl2, FeCl3, TiCl4, POCI3, SnCl4, SOCI2, n-butyl-SnCl3, and AIBr3. 23. The method according to claim 18, further characterized in that the activating component comprises at least one compound selected from the group consisting of AIBr3, AICI3, FeCI2 and FeCI3. 24. The method according to claim 18, further characterized in that the activating component comprises at least one compound selected from the group consisting of AIBr3 and AICI3. 25. The process according to claim 18, further characterized in that the activating component consists of a compound selected from the group consisting of FeCI2 and FeCI3. 26. The method according to claim 10, further characterized in that the oxidizable component comprises aluminum. 27. The process according to claim 26, further characterized in that the activating component contains a halogenide. 28. The method according to claim 26, further characterized in that the activating component is a metal halide. 29. The process according to claim 26, further characterized in that the activating component is a halogen compound hydrolysable in protic solvent. 30. The process according to claim 26, further characterized in that the activating component comprises at least one compound selected from the group consisting of AIC! 3, FeCl2, FeCl3, TiCl4, POCI3, SnCl4, SOCI2, n-butyl- SnCI3 and AIBr3. 31. The process according to claim 26, further characterized in that the activating component comprises at least one compound selected from the group consisting of AIBr3, AICI3, FeCI2 and FeCI3. 32. The method according to claim 26, further characterized in that the activating component comprises at least one compound selected from the group consisting of AIBr3 and AICI3. 33. The method according to claim 26, further characterized in that the activating component consists of a compound selected from the group consisting of FeCl2 and FeCb. 34. The method according to claim 1 further characterized in that the oxidized form of the oxidizable component is reduced from a higher oxidation state, in a chamber selected from the group consisting of the same chamber in which the oxidizable component is placed in contact with the activating component, and a chamber connected to the chamber in which the oxidizable component is brought into contact with the activating component. 35.- The process according to claim 34, further characterized in that the activating component contains a halide. 36.- The method according to claim 34, further characterized in that the activating component is a metal halide. 37.- The method according to claim 34, further characterized in that the activating component is a halogen compound hydrolysable in protic solvent. 38.- The method according to claim 34, further characterized in that the activating component comprises at least one compound selected from the group consisting of AICI3, FeCl2, FeCl3, TiCl4, POCI3, SnCl4, SOCI2, n-butyl-SnCl3 and AIBr3. 39.- The method according to claim 34, further characterized in that the activating component comprises at least one compound selected from the group consisting of AIBr3, AICI3, FeCI2 and FeCI3. 40. - The method according to claim 34, further characterized in that the activating component comprises at least one compound selected from the group consisting of AIBr3 and AICI3. 41. The method according to claim 34, further characterized in that the activating component consists of a compound selected from the group consisting of FeCI2 and FeCI3. 42. The method according to claim 34, further characterized in that the oxidizable component comprises at least one compound selected from the group consisting of an oxidizable metal and oxidizable metal alloy. 43.- The method according to claim 34, further characterized in that the oxidizable component comprises at least one compound selected from the group consisting of an oxidizable metal and oxidizable metal alloy, wherein at least one metal is selected from the group which consists of iron, aluminum, copper, zinc, manganese and magnesium. 44. The method according to claim 43, further characterized in that the activating component contains a halide. 45.- The process according to claim 43, further characterized in that the acifivating component is a metal halide. 46. The method according to claim 43, further characterized in that the activating component is a halogen compound hydrolysable in protic solvent. 47.- The method according to claim 43, further characterized in that the activating component comprises at least one compound selected from the group consisting of AICI3, FeCl2, FeCl3, TiCl4, POCI3, SnCl4, SOCI2, n-butyl-SnCl3, and AIBr3. 48. The method according to claim 43, further characterized in that the activating component comprises AIBr3, AICI3, FeCI2 and FeCI3. 49.- The method according to claim 43, further characterized in that the activating component comprises at least one compound selected from the group consisting of AIBr3 and AICI3. 50.- The method according to claim 43, further characterized in that the activating component consists of a compound selected from the group consisting of FeCI2 and FeCI3. 51.- The method according to claim 34, further characterized in that the oxidizable component comprises iron. 52. The method according to claim 51, further characterized in that the activating component contains a halogenide. 53. The method according to claim 51, further characterized in that the activating component is a metal halide. 54. The process according to claim 51, further characterized in that the activating component is a halogen compound hydrolysable in protic solvent. 55.- The method according to claim 51, further characterized in that the activating component comprises at least one compound selected from the group consisting of AICI3, FeCl2, FeCl3, TiCl4, POCI3, SnCl4, SOCI2, n-butyl-SnCl3 and AIBr3. 56.- The method according to claim 51, further characterized in that the activating component comprises at least one compound selected from the group consisting of AIBr3, AICI3, FeCI2 and FeCI3. 57.- The method according to claim 51, further characterized in that the activating component comprises at least one compound selected from the group consisting of AIBr3 and AICI3. 58.- The method according to claim 51, further characterized in that the activating component consists of a compound selected from the group consisting of FeCI2 and FeCI3. 59.- The method according to claim 34, further characterized in that the oxidizable component comprises aluminum. 60.- The method according to claim 59, further characterized in that the activating component contains a halide. 61.- The method according to claim 59, further characterized in that the activating component is a metal halide. 62. The method according to claim 59, further characterized in that the activating component is a halogen compound hydrolysable in protic solvent. 63.- The method according to claim 59, further characterized in that the activating component comprises at least one compound selected from the group consisting of AICI3, FeCl2, FeC, T1CI4, POCI3, SnCl4, SOCI2, n-butyl- SnCI3 and AIBr3. 64.- The method according to claim 59, further characterized in that the activating component comprises at least one compound selected from the group consisting of AIBr3, AICI3, FeCI2 and FeCI3. The method according to claim 59, further characterized in that the activating component comprises at least one compound selected from the group consisting of AIBr3 and AICI3. 66. The method according to claim 59, further characterized in that the activating component consists of a compound selected from the group consisting of FeCl2 and FeC-67.- The method according to claim 1, further characterized in that the oxidizable component comprises cobalt. 68. The method according to claim 67, further characterized in that the activating component contains a halide. 69.- The method according to claim 67, further characterized in that the activating component is a metal halide. 70. The process according to claim 67, further characterized in that the activating component is a halogen compound hydrolysable in protic solvent. 71.- The method according to claim 67, further characterized in that the activating component comprises at least one compound selected from the group consisting of AICI3, FeCl2, FeCl3, TiCl4, POCI3, SnCl4, SOCI2, n-butyl-SnCl3, AIBr3 and C0CI3. 72. The method according to claim 67, further characterized in that the activating component comprises at least one compound selected from the group consisting of AIBr3, AICl3, FeCI2 and FeCI3. 73.- The method according to claim 67, further characterized in that the activating component comprises at least one compound selected from the group consisting of AIBr3 and AICI3. 74.- The method according to claim 67, further characterized in that the activating component consists of a compound selected from the group consisting of FeCl2 and FeCb. 75.- The method according to claim 1, further characterized in that the oxidizable component comprises iron and the activating component comprises AICI3. 76. The process according to claim 1, further characterized in that the oxidizable component consists essentially of iron, and the activating component consists essentially of AICI3. 77.- A process for the manufacture of an oxygen scavenging particle wherein the particle comprises at least one oxidizable component and at least one activating component, and said method comprises contacting the activating component with a gas containing a vapor of the oxidizable component, and depositing the oxidizable component of the gas on the activating component in liquid or solid form.